One of the major drawbacks of the diesel engine is the amount of smoke that is created. The fuel injectors used in traditional diesel engines were driven by cams powered by the engine itself. This resulted in a fuel pressure that was proportional to the engine speed, resulting in much of the smoke. A device has recently been developed that will significantly reduce the smoke. A rail fuel-injection system has been developed that uses a high-pressure pump to supply fuel to a common distribution pipe. This pipe supplies fuel to piezoelectric solenoid valves that inject fuel into the engine cylinders at high pressure independent of the engine speed. The result is that the fuel burns much better, providing a “smokeless” diesel engine that performs well at all speeds